It is a huge blow for Reus, who enjoyed an excellent season for Borussia Dortmund, scoring 20 goals as they finished second in the Bundesliga and reached the quarter-finals of the Europa League, where they were beaten in dramatic fashion by Liverpool.

The forward, who missed the 2014 World Cup through injury, has been struggling at the team’s training camp in Ascona, Switzerland, and Löw has ultimately decided the 27-year-old would struggle to get through a one-month tournament.

“He has huge health problems and can only run straight at the moment,” said the head coach. “The medical staff could not give a clear prognosis for Marco. He has massive injury problems and the medical staff was very sceptical about his ability to last through the coming weeks and such a gruelling tournament.

“It is a bitter decision and bitter for Marco,” he said.

Reus’s Germany team-mate Sami Khedira said: “You have to be fully fit if you play in a European championship. It is very bitter but I am confident he will get his chance on the big stage. He was very calm and composed in accepting the decision.”

Löw has also cut the 20-year-old midfielder Julian Brandt from his final 23-man party, as well as Brandt’s Bayer Leverkusen team-mate Karim Bellarabi and Hoffenheim midfielder Sebastian Rudy.